In 2002, the sequel to Rollercoaster Tycoon, that being Rollercoaster Tycoon 2 was released, bringing in new features to the base RCT experience in addition to new rides, such as a track designer and scenario editor. In addition to the two official expansion packs Wacky Worlds and Time Twister, numerous custom content was released during the 2000s, even after Rollercoaster Tycoon 3 was released, and continues to recieve custom content to this day. With the release of OpenRCT2, the gameplay of Rollercoaster Tycoon 2 has been expanded receiving quality of life improvements and later new formats that increases the limit of vanilla RCT2.
However, not all custom content for RCT2 is available these days, as many have become lost media like the many downloads from RCT Mart. And one example is the donation-exclusive RCT2 scenarios from Nancy's RCTycoon Resource, which was a supplement to the author's custom scenarios that could only be acquired by donation via PayPal or writing to the author.
So far, as of today, no one has provided links to the extra scenarios from Nancy's RCTycoon Resource, and it's unlikely that any surviving copies of the scenarios are known to exist.
If you have a copy of the scenarios, let me know about this.